I am the new owner of a 1973 Ambassador, which has what appears to be the original Dometic gas/electric refrigerator. Turned it on to the electric and did not think it was working, as there was no noise or change at all - but things got cold and there was ice in the freezer. After a few days, I turned off the electric to the trailer to see what still worked, as the hum from the Univolt can be annoying. When I turned it back on, the refrigerator no longer would get very cold or make ice. We tried the propane, and it seems to be the same situation - the freezer gets noticeably colder but no ice forms and the refrigerator does not get cold. There is no noise of anything happening, all is quiet in the fridge. I don't know why it was working, albeit silently, and now is not when it is still exactly where it was and nothing has changed that I know of. But I don't know if it is supposed to hum and make some noise when it is cooling. ??

I am the new owner of a 1973 Ambassador, which has what appears to be the original Dometic gas/electric refrigerator. Turned it on to the electric and did not think it was working, as there was no noise or change at all - but things got cold and there was ice in the freezer. After a few days, I turned off the electric to the trailer to see what still worked, as the hum from the Univolt can be annoying. When I turned it back on, the refrigerator no longer would get very cold or make ice. We tried the propane, and it seems to be the same situation - the freezer gets noticeably colder but no ice forms and the refrigerator does not get cold. There is no noise of anything happening, all is quiet in the fridge. I don't know why it was working, albeit silently, and now is not when it is still exactly where it was and nothing has changed that I know of. But I don't know if it is supposed to hum and make some noise when it is cooling. ??

One of the beautiful things about an RV refrigerator, also known as an ammonia absorption, refrigerator is that they make no noise either on electric (110V) or gas.

It sounds like the refrigerator was working correctly at the beginning. Try again on electric and unplug the univolt if the humming bothers you. You don't need it running to keep the refrigerator working.

I am the new owner of a 1973 Ambassador, which has what appears to be the original Dometic gas/electric refrigerator. Turned it on to the electric and did not think it was working, as there was no noise or change at all - but things got cold and there was ice in the freezer. After a few days, I turned off the electric to the trailer to see what still worked, as the hum from the Univolt can be annoying. When I turned it back on, the refrigerator no longer would get very cold or make ice. We tried the propane, and it seems to be the same situation - the freezer gets noticeably colder but no ice forms and the refrigerator does not get cold. There is no noise of anything happening, all is quiet in the fridge. I don't know why it was working, albeit silently, and now is not when it is still exactly where it was and nothing has changed that I know of. But I don't know if it is supposed to hum and make some noise when it is cooling. ??

The reefer is absolutely quiet when running on electric or LPG, as there are no moving parts.

Keep in mind, that the reefer, when sitting still, must be within 1/2 bubble of being level.

The measuring place for that is the freezer plate, which in your case, is the small shelf in the freezer.

If the reefer was not close to being level, you could have "vapor locked" it.

Leave the reefer off for a couple of days and try it again.

If still not working correctly, again, leave the reefer off for a couiple of days, and then tow the trailer for a few miles. Then try it all over again.

Thanks to everyone for all the input. I went back to the electric, which made some cold in the freezer but not enough. I turned it all the way to max and it made ice in the freezer but not ice cubes. There is nothing apparently going on in the refrigerator part. I was lucky enough to get all the manuals with the trailer, and one of the first troubleshooting things for this problem is checking the vent for blockage - but I can't see any simple way to do that. Is this something that should be done and if so, how??
I see in the manual that there is a fill cap on the back. Is this something that needs filling with something? Ignorance is awful.
Thanks again, All.
Greg

Thanks to everyone for all the input. I went back to the electric, which made some cold in the freezer but not enough. I turned it all the way to max and it made ice in the freezer but not ice cubes. There is nothing apparently going on in the refrigerator part. I was lucky enough to get all the manuals with the trailer, and one of the first troubleshooting things for this problem is checking the vent for blockage - but I can't see any simple way to do that. Is this something that should be done and if so, how??
I see in the manual that there is a fill cap on the back. Is this something that needs filling with something? Ignorance is awful.
Thanks again, All.
Greg

Hi Greg,
Welcome to the forum. This is the place that answers come to find people in search of them.
The vent is on the roof, and you need to clean out any leaves or other debris so it will get maximum airflow, and to help prevent the possibility of a fire, which is not likely but possible. Also clean under the refer and behind it, including the coils.
There is nothing for you to fill, except to fill the refer with beer or other cool, refreshing beverages. You also should have an rv tech check the propane operation of the refer, to be sure it's all okay. There is a section in the forum about refers with lots of great info, well worth reading up on.

Well, if this is the place that answers come, I'm glad I landed here. The freezer's up to actual ice cubes now and the refrigerator is not dead warm. But it is set on Max, and it has been about 16 hours, so I guess it should be cold if everything was working right? Anyway, I had checked the vent on the roof, and there doesn't seem to be any way to do anything but look at it or feel a little around the top, as it is roofed over to within an inch of the top of the vent stack. We have a lot of mud daubers, so this is always a possibility, but how to check or get into it? Also, is moving the refrigerator out a big project involving taking out the wall next to it, etc.? Or is there an easy method? Can't see under or behind it otherwise.

You should have an exterior access door or two that allow access to the back and bottom. Some refers have a removable toe kick plate at the bottom, front also. You may be able to remove the top cover from the roof vent to allow you to see and clean inside it. Mine was screwed on, yours may be riveted.
The refer in mine was attached to the floor with four large bolts, and to the counter top above it with screws. Not all of them were done the same, so you will need to look at yours and locate the fasteners if you decide to remove it.
Before doing that you should place a thermometer in the freezer and refer to document the temps you are achieving.